Current wireless mobile communication devices include microprocessors, memory, soundcards, and run one or more software applications. Examples of software applications used in these wireless devices include micro-browsers, address books, email clients, and wavetable instruments. Additionally, wireless devices have access to a plurality of services via the Internet. A wireless device may, for example, be used to browse web sites on the Internet, to transmit and receive graphics, and to execute streaming audio and/or video applications. The transfer of Internet content to and from wireless device is typically facilitated by the Wireless Application Protocol (“WAP”), which integrates the Internet and other networks with wireless network platforms.
On a constrained device such as a wireless device, memory is often in short supply. The number of email messages that a wireless device can store is sometimes used as a selling feature of the device. The new features and applications that are being introduced for wireless devices take up more memory space and hence reduce the number of email messages that a user can store. Users find it annoying to have messages erased from their device because there is a lack of memory space.
One method of saving memory space is to use compression techniques to compress the email message bodies. On average, this can double the number of messages that the wireless device can hold. However, a typical message list for a user has many threads of messages. A message thread is a sequence of messages relating to the same topic. A simple message thread includes messages that switch back and forth between two recipients much like a conversation. Typically, each message in the thread contains the message text from the body of the message that the user is replying to. The longer the thread goes on, the longer the original text of the message is, and the more memory space each reply uses. The same text appears multiple times over the message thread, but since the text appears in different messages, current compression algorithms are not able to take advantage of the redundancy between the messages.
Therefore, one shortcoming of present wireless devices and wireless communications systems is their inability to efficiently store email message threads. This is especially so as the capabilities of different wireless devices vary and the amount of resources (e.g., flash memory, remaining carrier-enforced data limits, etc.) available is limited and constantly changing due to the arrival of new messages, calendar appointments, etc. Moreover, the need to efficiently store email message threads is increasing in importance with the increase in the number of applications being run on wireless devices.
A need therefore exists for an improved method and system of storing email message threads in wireless and other devices. Accordingly, a solution that addresses, at least in part, the above and other shortcomings is desired.